Nobody with half a brain leaves money in an exchange. If you want to purchase from an exchange, it takes about 4 seconds from $USD - LTC or $USD - BTC, and then you transfer to your crypto wallet. The only person who has access to my crypto currency is myself. It lives in my cell phone, and on a USB drive.

a u.s. dollar bill or a coin today is a respresentative for something of value, gold, silver,,,,,,and a promise to pay in such kind.

please educate me [seriously here] as to what is the tangible thing of value backing of the bitcoin?

The moar you now:

"By 1970, the U.S. only held $14.5 billion in gold against foreign dollar holdings of $45.7 billion. On August 15, 1971, President Nixon changed the dollar/gold relationship to $38 per ounce. More important, the Fed stopped redeeming dollars with gold. The U.S. government repriced gold to $42 per ounce in 1973, and then decoupled the value of the dollar from gold altogether. The price of gold quickly shot up to $120 per ounce in the free market. (Source: Time, Fuss Over Dollar Devaluation, October 4, 1971)

Once the gold standard was dropped, countries began printing more of their own currency. Inflation usually resulted, but for the most part abandoning the gold standard created more economic growth.

However, gold has never lost its appeal as an asset of real value. Whenever recessions or inflation looms, investors return to gold. It reached its record high of $1,895 an ounce on September 5, 2011. "

Do you believe that Fiat not backed with gold is a scam? Do you think gold is a scam?

honest short answer...because it lives in cyber world. In realitly all money is a scam and so are economies. My dollar is worth a dollar because other people accept it as a dollar. Nothing more, nothing less. Bitcion is worth something, because people believe it is worth something and will accept it. I'm not ready for that, to me its worth nothing

what did that one guy say, warren buffet I think, be greedy when others are fearful and fearful when others are greedy.

He also said

"No. 5: Don't put your money into Bitcoins for the long run"

"It's not a currency. It does not meet the test of a currency. I wouldn't be surprised if it's not around in 10 or 20 years. ... It is not a durable means of exchange. It's not a store of value. ... It's been a speculative — a very speculative — kind of Buck Rogers-type thing, and people buy and sell them because they hope they go up or down just like they did with tulip bulbs a long time ago."